That upper in those pics are nice Dobs!

I might consider Braceman, but I might test one upper with my local machinist. He does custom slides for my 3-Gun friends. I have not decided yet, as I'm still in the market for one more receiver. I have a lead on a few, but already spent a lot of money on other rare goods, so we'll see.

Now that you have a closer picture of the 14th slot, I am still convinced that it is still not truly in spec. But it looks like to me in the 90%-95% range, and you still could mount a back up iron sight. I cannot stress enough on how much Braceman did a fantastic job despite the precious 13 slot positions on a M4 spec rail. The Canadian spec slots are slightly forward to make room for the 14th slot.

Yeah I agree completely. Unfortunately with the spacing set the way it is in the US spec upper, I think what Braceman has done is about the best you're gonna get out of a US spec without starting from a 0% forging. Again I am not a machinist, so I could be completely out of the park with that. But with the upper I got from you being a Diemaco\Cerro and them being pretty hard to find, I wouldn't have trusted it with anyone but Elucidate or Braceman honestly. All in all it's damn good for what it is. If you get your hands on any true Canadian spec uppers and you want to off one, let me know!

Braceman had a 100% real, issued to the SAS upper to clone from for the work he is doing to these uppers. I know because I sent it to him!

A couple of things to consider

* A Canadian Weaver spec rail is different to the UK spec rail on the upper. UK spec are real 1913 rails.

* The height of the UK spec rail is higher than a Canadian one, it is the same height as the US F marked FSB size rails.

* The difference between a US upper rail and the UK spec is that on a UK upper, the gap between the front of the receiver and the start of the first rail is 9.7mm, on a US spec upper its 11.6mm. This is why the spacing is ever so slightly off when you add the last slot, as you need to keep the rail spacing the same, so it's 2.1mm offset from a UK rear slot.

* This is THE most accurate you can make a US spec upper, which given the complete lack of Canada spec uppers being available, is basically the best we can get. It is actually better than the Canadian upper I think as they don't use the correct height rails if you're going for accuracy and also of course it's much easier to find/source F marked FSBs here.

I'm happy as hell with mine! When I financially recover from my recent build project, I'm gonna send you my lower for matching ano!

I probably should clarify myself by emphasizing the differences in Canadian spec uppers. Every time I mention "Canadian spec," I usually use it as a generality regarding uppers that use a front chamfer, rear scallop, and a 14th slot. There are two versions of a Canadian spec upper receiver: Canadian Weaver and Canadian 1913.

Canadian Weaver was based on a Weaver rail with Dick Swan of ARMS helping with the dovetail design. Like what Elucidate says, it sits lower than the M4 rail. this upper would see extended use by Canada, Denmark, Norway and the Netherlands. It made sense for Canadians to stick with the Weaver rail because of the iron sights optimized for the Weaver rail, and their optics built for it. These are the same uppers that were previously used on the C7A1 (and later reused on the C7A2) to this day.

Canadian 1913 is an upper that was made from M4 style upper forged blanks out of the request by some countries (and by Colt if I'm not mistaken). These uppers were seen in CAF service on the C7CT and C8CT rifles, and it is the exact same upper used on the L119 and L119A1. Some time after Colt's acquisition of Diemaco, they slowly moved over to standard 1913 for building new rifles (with the exception of some contracted service rifles and domestic rifles like the C7A2). Every rifle from Colt Canada today would be made with the 1913 upper, and recently, the Diemaco Devtek D forge code would be replaced with a raised forge code being Colt Canada's cage code 2C085 (The IURs would have only the Brass Aluminum forge code with a stamped "NATO," with the name and cage code on the other side, but that is probably irrelevant to this forum).

The only Weaver rail uppers that you can visually see would probably be being enlisted in the Canadian Armed Forces, and attempting to clone one would be nonsensical because they look extremely similar that only can be told apart by close comparison with both uppers and using measurement tools.

I took Elucidate's measurements and confirmed it with my uppers out of curiosity. For visual reference, the photo below shows the difference between a Diemaco M4 spec upper with a Colt Canada 1913 spec upper. You can see the rails are slightly off.



Back to the 14th slot hubbub, because the US spec rails were further back on the receiver, I thought there would not be enough room on the stripped Colt/Diemaco uppers (although there are some uppers with long enough dovetail for a 14th slot, no stripped Diemaco upper take-off did). I always tried to eyeball it, but I have always sworn that there might not be enough space in the rear of the receiver. I also thought the photos provided by Dobs might have shown a shorter slot or smaller notch. It must be an optical illusion, because when I put it in a computer with measurements, it looks like it has more than enough room to mimic a correct 14th slot as shown in the next photo. (The green lines are a demonstration to show that the receivers are misaligned to properly match up the rail slots)

To close out the subject of the British Diemaco 1913 rail versus what you can make from US parts, here are some pictures of a John Brace modified upper against an actual real issued British upper.

Here is the front, showing the aforementioned slight offset between where the slots begin. These uppers are aligned perfectly both front and rear to illustrate exact differences.



Here is a close up of the rear, showing the John Brace rear scallop perfectly matches the UK issue rear scallop and the additional slot milled into the rear.



Here is a zoomed out overall view



The upper used here is a standard M4 upper which I procured in the raw so that the anodizing would be perfect. Before it was anodized I sent it to John Brace along with the original, hence the as close as possible results. The only real difference is the new upper has M4 cuts in the upper, thus it actually works better with US barrels.

Ah... With the pictures, this gives me a whole new perspective. John mills the rear scallop based on the exact dimensions of the 1913 upper. The "lip" in the back of the receiver (can we even call it that?) is longer because the M4 spec cuts into the receiver more, thus the top rail on the Canadian 1913 is longer. I always noticed that, but I though it wasn't worth bring up. I personally would have the scallop be milled further into the receiver, despite it being a millimeter off to give the illusion of a Canadian/British upper.

$5800?

Here's mine.

The receiver/rail dimensions are interesting. It appears there was some variation in exactly what was being issued at different times. It would be cool to put together a timeline of known-issued L119A1 uppers but there just isn't a ton of information out there that I could find. Elucidate, I think this is the most comprehensive collection of this stuff that I've seen, thanks for putting it together.

Hey, Mkmckinley. Where can I get those non-F marked front sights (with the bayo lug) with the "crown" forge codes? I need them for my classic C7 and C8 projects. I already have a Colt A2 HBAR front sight with bayonet lug shaved off at the factory for my L119A1. (It's already got a great early "Colt grey" on it as well!)

You're going for the trifecta? I'm not sure where you could get those parts on the commercial market or if it's even possible to buy them. I've never seen any for sale but Elucidate seems like the authority on that stuff. I honestly didn't know people were building replicas of these things until I saw this thread.

It's hard to find the right forge codes for any part to make a rifle period correct.

And for the trifecta? More so... Let's just say that I have become pretty ambitious the last year.

You probably know a lot more about it than I do. After going over this thread here's what I've been able to come up with: The upper has forge codes similar to the ones in your post above, the second picture down on your post from 4/26/2018 and it's marked "M4" in front by the gas tube port. The "A" is about 1/3" in front of the "D" for lack of a better term. The barrel is marked "5.56" on the right side under the FSB and it has a US spec RAS. Based on what I'm reading here I'm not sure if this is an earlier or later configuration. It's a bring-back from Helmand about 10 years ago so no later than about 2009 give or take. If anyone has any more info or can suggest other markings to look for etc. I'm all ears.

I managed to gather more parts, and I got some more on the way. I'll post photos soon.

I just bought a 10” SAS IUR barrel.

What else can you tell me about it? Why that length and not 10.3” or 10.5”?

Can I still use my Geissele Mk8 rail on this build?

What is the length of the rail/handguard in inches on the 10” IUR upper?

Providing the AR-15 upper is a standard mil-spec, using that barrel with any barrel nut with mil-spec dimensions should not be a problem. I think the Geissele Mk8 (9.5) is about as long as an IUR "handguard," even though it truly a monolithic rail and the point where the "receiver" becomes the "handguard" is pretty much non-existent. You can use the Geissele Mk8 with the 10" barrel, but it will not be clone correct. I believe it is possible to clone a L119A1 to some degree in Canada, after all, you have a Colt Canada 10" barrel. A C8-CQB upper would be a perfect starting point since they both use the Diemaco 1913 upper. If you want to clone the L119A2, just buy a SAS IUR.

You can find more info on the SAS L119A2 here.

I managed to get more parts for my L119A1 build. I'll spare you all the (mostly) Colt parts where I could not find Diemaco parts. Besides a few lower components like the gas tube, spings, detents, etc. the big things that prevent me from completing my builds are a L119A1 engraved lower and a barrel. I have been buying other Diemaco parts for other guns and they tend to be a bit more $$$. I am going to have to recover from my Diemaco shopping before I can jump on a barrel and lower.

I am just going to cover over the "unique" parts that stand out on the L119.

The parts I have gathered are:

- Colt CAR-15 castle nut (not pictured)
- Diemaco front sight post (not pictured)
- Diemaco M4 upper
- Diemaco bolt carrier group
- Diemaco C8 2-pos buffer tube
- Diemaco early HH buffer
- Colt Canada buttstock (black pebble grain texture)
- Surefire FH556-216a (current production)
- Colt AR-15A2 HBAR competition front sight (non-F marked)
- early Stag Arms safety (enlarged A2 tick mark)
- older KAC RAS set for L119 (w/ SAS bottom rail) [marked 1-13]
- KAC Vero Beach, FL panel (more on the way)
- Lone Star Ordnance stowaway grip
- Warlord Tactical L119 endplate



(Sorry for the crappy quality on some photos)

I originally had a C8 take-off receiver extension lock ring (CAR castle nut), but I set it aside for a buddy for a trade. So I went ahead and got a Colt made CAR castle nut that had some of it parkerization worn off (it's going to get reparkerized anyway). I have a spare C8 buffer tube with a really worn finish, so I am currently debating on having the threads milled off with a lathe then recoated with Elucidate's Colt Canada grey. Diemaco milled exposed threads between the tubes locking tabs and where the castle nut meets. This is a process done on the C8A1 and all models onward.

As I was able to track down a Stag arms tick safety (thanks Dobs013!), I decided to discared the High-Standard safety since the "tick" didn't meet my standards. But it's jet black and has finish wear with a sheen on the tick side? No problem, getting the anodizing treatment! I also have acquired an older version of the HH buffer. Top photo is the older HH and the bottom is the newer HH.

Older (Yellow end cap)


Newer (White end cap)


I also managed to get a Colt AR-15A2 HBAR competition .750 front sight that is non-F marked. What I find interesting is that it's sporting the early Colt grey and has the bayonet lug shaved off for me by the factory. Saves me the trouble of using the grinder! As for the endplate, I am aware it has no "protrusion" to fit flush with the lower rear socket to prevent rotation and I am currently exploring options to modify it. In the meantime, I have a buddy that has a scout in the UK that is looking for one. If that falls through, I'll get in contact with my buddy's Colt Canada contact. It's a long shot but I don't manage to get the real endplate, I am perfectly fine with that because these endplates are manufactured out of unobtainium.

I also managed to score a 1-13 marked KAC SAS handguard set. Previously I purchased a SAS lower and I noticed a difference...




I believe the (newer) left SAS lower rail on the right in the bottom picture is labeled 16-28 and is ordered in line with a T-marked M4 upper. The right lower rail is marked 1-13 and is ordered in the opposite direction with the assumption that there is no T-markings on the upper receiver. Are the 16-28 rails issued on the Royal Marines L119A1? Or is this a recent production change? Anyway, I sold the (possibly bought on KAC web store) 16-28 SAS rail and I'll use the 1-13 marked set. Just though I mention it.

Interesting, would love to know the answer here.

I am working on a project very similar to the L119A1 but it will be just a C8CQB.  I was wondering if someone could answer a little technical question about the M4 RAS.  On KAC store you can buy the Canadian Edition or the standard and purchase the UK under rail separate.  When looking at the cost I could purchase the standard and the lower rail cheaper then the Canadian version.  Is there any difference in the two in regards to the TOP section?  it seems you US gents have more Diemaco then us up here, so I am going to be using the new Colt Canada upper receiver.  The new upper is 14 slot mil-std-1913. My other question is because of the slight difference between weaver and 1913, will the M4 RAS line up with my flat top receiver or will I have a "step" between them however small? (im not talking about the gap between the delta ring.)

Based on MSRP, it looks like you can save a whopping $100US by buying the standard set and the SAS bottom rail separately. I always found that interesting. Used KAC rails can always be found cheaper on the ARFcom EE. For Canadians, I don't know where you go to buy them, but I do know they are available up there. I can't answer if the markings are different if bought separately, but they should be the same markings of 14/16-28 on the top section. New production should be white markings, don't know about the matching screws of either being hex head or flat head.

From my experience, there should be no "step" on any Diemaco/Colt Canada upper that is marked 1913. They should line up just fine. Weaver rails only sit slightly lower where it is unnoticeable until you look very closely.

I do believe it is possible to acquire a Devtek D upper in Canada from surplus C8-CQB uppers instead of the newer C2085 uppers. In the US, all we can resort to is Colt USA made uppers on Diemaco forgings with the Devtek D.

Not sure If I have shared these pics, but it shows the differing manufacturing processes used by Colt Canada.

If you look closely here you'll see the model markings are laser engraved and not stamped like Colt USA. The serial number is stamped, they use a big stamping wheel for that.

This picture also shows the UK spec ACOG, which has some different markings, no bible stampings and a big UID sticker.



Here is a close up of one of the lowers

Canadians can get most KAC products brought in by Calgary Shooting Center now, who seems to have taken over imports of their products after the last guys who actively stocked them went under.  Last I checked, M4 RAS was running 410 CAD, and SAS/CAN model was going for about 700 CAD.  Expensive shit right now for us.

Do you know if the carbines have UK proof markings? I owned a sabre defense
20" rifle, and the crown markings were on the barrel and bolt.

Yes, even Military rifles are proofed.

Great thread.

I had a good talk with some of the Colt Canada engineers at SHOT either this year or last.

They said they don't do the same things the US M4 TDP calls for on the bolt.  They cocked an eye when they heard about bolt failure in USSOCOM guns, because they just weren't seeing it really with the Diemaco guns after decades of heavy use with SAS, SBS, and CanSOF units.

They follow different processes to ensure a long-lasting bolt, as opposed to US DoD TDP for the M4 bolt proof load-testing.

Bill Alexander (who used to work for UK MoD) said that he and other companies prefer not to do HPT across the lots because of the micro fractures it induces, which can only propagate from then-on, leading to early failure.

Instead, he prefers to do batch testing with destructive processes on a percentage of the bolts, proof load those, then MPI, then grind the faces off and immerse in resin to see grain structure alignment.

If there are issues with that percentage, you test more in the batch and reject or pass based on what you see.

KAC prefers not to HPT the SR25 bolts as well, whereas against all recommendations from people that knew better, the Army still demanded it on the M110 SASS.

Guys in Ranger Regiment who used both systems said they had bolts breaking on M110s all the time, but not SR25s.

There is value in those Colt Canada bolts, and they will last very long in an upper with the receiver face squared.

bumping this thread back up for any new pics/info

i'm still gathering parts for my build

Who makes and where can we get the Diemaco-like black buttpad shown on p. 4?

Elucidate,  just wonder if you have a picture of your rifle complete?  I am building my clone but unfortunately I will be using new CC parts.  Trying to get Diemaco here in Canada will cost an arm and a leg.  The barrel has been the hardest part for me to source.  I didn't want to use just any barrel and after a few years of searching have finally found a dealer to help me get a factory new 10" CC.

One more question,  I haven't picked up the KAC rail yet but it will be added to my build.  Would you have been content with just a standard M4 rail or for you did it make all the difference that it is the UK version.  The M4 RAS is $400 CAD and the UK is $775 CAD. When I hit 50 posts I will post my L119A2 in the other thread.

Great thread, the attention to detail is outstanding.

I saw this knights rail on gunbroker;

https://www.gunbroker.com/item/786796751

Looks to be the correct one for this build.

Question on the ACOG used on this carbine, is the reticle calibrated for the 10 inch barrel and ammo used?

lol yeah at twice the price they go for used on ee and fleabay....

I used the UK version. Not sure anyone could tell without being a huge nerd.

Those are the 3 different styles of end plates.

Here's Brad's from Nordic Marksmans CSOR C8 build. I had the opportunity to buy a genuine CSOR upper, a few were leased to the public, but they were $3200CAN.

This is a build on my list!

Did we figure out a place to find those correct looking selectors?

When we compare our Colt Canada ambi selector, it looks identical to a Colt USA ambi selector, using one long and one short lever. It should be reversible, so that you can choose which side the long/short lever sits on.

It looks like Charlies customs has them listed currently.

I was looking for the non ambi. With the correct tick mark.

Mine came from a Stag arms parts kit.

Just so everyone is aware. The lpk I received from stag today did NOT have the USGI tic mark.

Also, their USGI silent slings, might fit around a teenager.

my build has kind of stalled , i have 3 other builds in front of it.  i've actually been thinking of moving it to help fund the builds in front of it

with F1's going as quick as they have been lately though it's got me thinking about just submitting for the stamp and bumping it up the build list and finishing it up.

here's what i've collected so far

Curious about where you found a dealer who can source the 10" CC's.  If you're able to share it, please send me a PM with the details.  Been looking into doing two CANSOF clones, and I'd rather not have to get the barrel on a 15.7 chopped just to do the older style.  Also, are your prices listed for the KAC rail from Calgary Shooting Center?  Thanks from a fellow Canadian.

Innapropriate post. Sorry.

Very nice thread! I just picked up a CC IUR 3rd Gen 15.7. It's an overrun from the British Contract. Now I have to hunt down all the other CC goodies

So I have a Surefire FH556-216A sitting in the parts box. It doesn’t have the “jagged teeth” on the inside of the tines. Is this a later production? What suppressor mounts to it?

FFA556SA obviously.

HA! I figured that out.

From my collection that might be of interest ...